1. Field of the Invention
This invention generally relates to caulking devices ("guns") of the type that use expendable caulking compound cartridges having nozzles whose tips need first be snipped off prior to use, and subsequently trimmed to provide a larger bead of the caulking compound or even cut on the bias (slanted) as desired by the user of the tool. Furthermore, this invention relates to any device containing a cartridge that dispenses a medium for any purpose, such as sealing or insulating, and can even be fabricated and marketed as a stand-alone device unattached to any dispensing mechanism and/or cartridge.
2. Description of the Prior Art
Many varieties of caulking guns exist, including those that provide an integral cutting device for snipping or trimming the nozzle tips of caulking compound cartridges, a necessary step prior to operating the caulking gun with an assembled cartridge. Typically, an aperture or hole is provided in a wall of the handle or hand grip; the aperture being configured and sized to receive at least a portion of the cartridge nozzle tip. In current art, a blade or cutting edge is attached to, or integral with, the trigger mechanism and is augmented by its normal pivoting motion, which when actuated to its fullest extent causes the blade or cutting edge to sweep past the aperture in the handle. The user need only insert the cartridge nozzle tip in the aperture and squeeze the trigger to snip the tip. Unfortunately, this snipping action occurs upon each and every trigger actuation, whether purposeful or inadvertent, and whether or not a caulk or sealant cartridge is installed. Hence the potential exists that someone unaware of the hazard, particularly a child, might insert his or her finger in the open aperture. Subsequent actuation, consequently, by anyone accessing the trigger could result in a serious injury.
For example, in U.S. Pat. No. 3,189,226 to Sherbondy, a shearing blade has a projection thereon which extends into a lost motion slot formed in one side of the trigger. The structure forms a shearing mechanism which is operable to trim the outlet end of a cartridge nozzle positioned in a hole in the handle. By pulling the trigger towards the handle, the blade is caused to move across the hole to shear off the end of the nozzle. A spring is provided for normally urging the trigger outwardly from the handle. In the normal or inoperative condition of the trigger, the cutting element clears the hole or opening in the handle to permit objects to pass through the hole or opening. This makes it possible for the user, or bystander, particularly a child, to pass a finger or fleshy part of the hand through the hole or opening prior to actuation of the trigger. Actuation, intentional or inadvertent, under those conditions, could cause serious injury.
A caulking gun is disclosed in U.S. Pat. No. 4,135,644 to Pacetti which includes a handle and an opening in the handle into which the nozzle of a caulking gun cartridge may be inserted. A knife blade is operatively attached to the trigger used to advance the ram that extrudes caulking compound from a cartridge. However, the caulking gun disclosed in this invention also normally exposes the opening provided in the handle through which a finger or fleshy part of the hand can pass when the trigger is fully extended. As with the previous patent, therefore, serious injury can result from misuse or inadvertence.
Another design of the caulking gun is disclosed in U.S. Pat. No. 4,390,115 to Bigham. Here, a plurality of holes of different sizes are provided in the handle of the gun, the holes being oval or elliptical in shape and having their edges beveled to form sharp edges on the inner side of the handle to act as a shear with a cooperating edge of the trigger when depressed into the handle. Aside from the shape of the holes, this caulking gun exhibits the same disadvantages or dangers inherent in the prior described designs, although, it may be that at least some of the smaller holes in Bigham may be too small for a finger or a fleshy part of the hand to pass therethrough. This is not the case in relation to the larger holes used in the disclosed caulking gun.
A tip trimmer assembly for a caulking gun is also disclosed in U.S. Pat. No. 4,802,607 to Johnson. One of its primary objectives is to provide a separate unit that can be used to retrofit existing caulking guns. Here, also, there is a cutting edge that sweeps over an aperture to snip the tip of a caulk cartridge nozzle therein inserted. This cutting edge may be detented in either open or closed aperture positions. In the former instance, the same hazard exists as for those configurations noted in the aforementioned patents.